1. Field of Invention
The present invention relates to a positioning vise, more particularly, to a rotating positioning vise for use in hand working operating such as hand engraving and stone setting in the hand engraving, hand carving and jewelry fields.
2. Description of Prior Art
The traditional hand engraving vise which has been in existence since the nineteenth century, consists of a ball base resting in a doughnut type cradle. The top half of the ball is made to pivot on a center axis. On top of this are the vise jaws. When the engraver or jeweler desires to hand engrave an arc on an object that is clamped in the jaws, he simply turns the vise with one hand while the other hand holds the engraving point on the surface of the object that is being engraved. The location of the rotating pivot position on the object being engraved can determine the difficulty of engraving an arc in the desired location. The location of the rotating pivot position depends on where the object is clamped in the jaws of the vise. An arc is easiest to engrave when it has its center location closest to the center pivot position of the rotating vise. Engravers and jewelers therefore become accustomed to having to unclamp, move and re-clamp the object many times in the course of a project. Unfortunately, clamping and unclamping to position the object in reference to the vise pivoting location can become a problem since the objects engravers and jewelers work on are often delicate and can be damaged if clamped incorrectly. In addition, a lot of time is wasted unclamping and clamping. Another example of the need to position a working area of an object in the center of a rotating vise is when delicate hand working operations are executed with a microscope. The microscope is centered over the rotating pivot position of the vise. The field of view through the microscope is limited and in order to keep a particular spot in view, the axis of rotation needs to stay in the center of the field of view of the scope, otherwise the area being viewed will swing out of view when the vise is rotated.
Disclosed in publication titled GRS POSITIONING VISE by GRS Corporation is a rotating positioning vise. The device utilizes a post though an oversized hole in a plate under the vise jaw apparatus. The vise jaw apparatus on top of the vise is made to slide around for positioning within the space between the post and oversized hole. The limitation to the apparatus is its limited movement between the post and hole. The nature of the design leaves little room between the post and oversized hole. The apparatus allows only one inch of movement off center. One inch is not enough room for movement if the engraver or handworker is working on an object any larger than this movement. Engravers, jewelers and handworkers therefore still have to unclamp and re-clamp in order to work outside the one inch radius area.
In more recent times engravers have employed turntables or lazy-susans with a vise set on top. The vise is simply pushed around on the turntable top for positioning. This works and gives a lot of movement for positioning although the vise is not solidly locked down on the turntable and can move at undesirable times. Also, this design does not allow tilting of the turntable to a more conformable position since the vise will slide off of the turntable if it is tilted. A similar adaptation to pushing a vise around on a turntable is to use a thin magnetic sheet material between the base of the vise and the turntable. The thin magnetic sheet material has a low enough magnetic power to allow it to be manually positioned and yet hold the vise in place. The problem and disadvantage that occurs in using magnetic sheet in this way is that positioning the vise is harder for the user, because it takes more force to break the magnetic force free to allow the vise to slide on the turntable. A lighter strength magnetic sheet can be used but then it does not have enough strength to hold the vise secure on the turntable.
A rotating positioning vise that allows a lot of freedom of movement is needed so that the user can accommodate, position and secure larger objects. The vise needs to rotate freely on its lower portion, and on top it needs a position apparatus that will allow it and the jaws to move together as a unit. This will allow the jaws and whatever is clamped in the jaws to be positioned and allow a desired portion of the object that the user is working on be in the center axis of rotation. Once the user positions the vise it needs to be locked securely in place to prevent it from moving during use. Engravers, jewelers, carvers and handworkers at times prefer to tilt their vise from side to side or towards them for comfort. Therefore, the vise should have a built in apparatus that allows the entire vise to be titled at will. The vise should have a locking mechanism for both the rotating turntable and positioning apparatus. The locking mechanisms should be easily and quickly locked and unlocked at will by the user.